1. Field of the Invention
This invention relates to cemented carbides, particularly in use in cutting tools. More particularly, it relates to a carbide having high strength at elevated temperatures.
2. Prior Art
Iron, nickel or cobalt are the binders used in conventional carbides that are used in cutting tools. These materials have good strength at lower temperatures and a high toughness. However, because of the low melting, relatively soft, ductile binders at elevated temperatures wear is high, deformation occurs and some thermal cracking occurs.
Attempts have been made in the past to employ Group 4, Group 5 and Group 6 metals as the binder, however, these materials suffered from high porosity and some segregation of materials therein. Fusion metallurgy led to materials having erratic tool life, also because of segregation and porosity.
It is believed, therefore, a material which does not have high porosity and is uniform throughout which employs a refractory metal as a binder would be a definite advance in the art.